/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/********************************************************************************
 * examples/kernel_sample/roundrobin.c
 *
 *   Copyright (C) 2007, 2008, 2012 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ********************************************************************************/

/********************************************************************************
 * Included Files
 ********************************************************************************/

#include <tinyara/config.h>
#include <stdio.h>
#include <stdbool.h>
#include "kernel_sample.h"

#if CONFIG_RR_INTERVAL > 0

/********************************************************************************
 * Definitions
 ********************************************************************************/

/* This numbers should be tuned for different processor speeds via .config file.
 * With default values the test takes about 30s on Cortex-M3 @ 24MHz. With 32767
 * range and 10 runs it takes ~320s. */

#ifndef CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE
#  define CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE 10000
#  warning "CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE undefined, using default value = 10000"
#elif (CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE < 1) || (CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE > 32767)
#  define CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE 10000
#  warning "Invalid value of CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE, using default value = 10000"
#endif

#ifndef CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS
#  define CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS 10
#  warning "CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS undefined, using default value = 10"
#elif (CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS < 1) || (CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS > 32767)
#  define CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS 10
#  warning "Invalid value of CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS, using default value = 10"
#endif

/********************************************************************************
 * Private Functions
 ********************************************************************************/

/********************************************************************************
 * Name: get_primes
 *
 * Description
 *   This function searches for prime numbers in the most primitive way possible.
 ********************************************************************************/

static void get_primes(int *count, int *last)
{
	int number;
	int local_count = 0;

	*last = 0;    /* To make the compiler happy */

	for (number = 1; number < CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE; number++) {
		int div;
		bool is_prime = true;

		for (div = 2; div <= number / 2; div++)
			if (number % div == 0) {
				is_prime = false;
				break;
			}

		if (is_prime) {
			local_count++;
			*last = number;
#if 0 /* We don't really care what the numbers are */
			printf(" Prime %d: %d\n", local_count, number);
#endif
		}
	}

	*count = local_count;
}

/********************************************************************************
 * Name: get_primes_thread
 ********************************************************************************/

static FAR void *get_primes_thread(FAR void *parameter)
{
	int id = (int)parameter;
	int count;
	int last;
	int i;

	printf("get_primes_thread id=%d started, looking for primes < %d, doing %d run(s)\n",
		   id, CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RANGE, CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS);

	for (i = 0; i < CONFIG_EXAMPLES_KERNEL_SAMPLE_RR_RUNS; i++) {
		get_primes(&count, &last);
	}

	printf("get_primes_thread id=%d finished, found %d primes, last one was %d\n",
		   id, count, last);

	pthread_exit(NULL);
	return NULL; /* To keep some compilers happy */
}

/********************************************************************************
 * Public Functions
 ********************************************************************************/

/********************************************************************************
 * Name: rr_test
 ********************************************************************************/

void rr_test(void)
{
	pthread_t get_primes1_thread;
	pthread_t get_primes2_thread;
	struct sched_param sparam;
	pthread_attr_t attr;
	pthread_addr_t result;
	int status;

	status = pthread_attr_init(&attr);
	if (status != OK) {
		printf("rr_test: ERROR: pthread_attr_init failed, status=%d\n",  status);
	}

	sparam.sched_priority = sched_get_priority_min(SCHED_FIFO);
	status = pthread_attr_setschedparam(&attr, &sparam);
	if (status != OK) {
		printf("rr_test: ERROR: pthread_attr_setschedparam failed, status=%d\n",  status);
	} else {
		printf("rr_test: Set thread priority to %d\n",  sparam.sched_priority);
	}

	status = pthread_attr_setschedpolicy(&attr, SCHED_RR);
	if (status != OK) {
		printf("rr_test: ERROR: pthread_attr_setschedpolicy failed, status=%d\n",  status);
	} else {
		printf("rr_test: Set thread policy to SCHED_RR\n");
	}

	printf("rr_test: Starting first get_primes_thread\n");

	status = pthread_create(&get_primes1_thread, &attr, get_primes_thread, (FAR void *)1);
	if (status != 0) {
		printf("         ERROR: Thread 1 creation failed: %d\n",  status);
	}

	printf("         First get_primes_thread: %d\n", (int)get_primes1_thread);
	printf("rr_test: Starting second get_primes_thread\n");

	status = pthread_create(&get_primes2_thread, &attr, get_primes_thread, (FAR void *)2);
	if (status != 0) {
		printf("         ERROR: Thread 2 creation failed: %d\n",  status);
	}

	printf("         Second get_primes_thread: %d\n", (int)get_primes2_thread);
	printf("rr_test: Waiting for threads to complete -- this should take awhile\n");
	printf("         If RR scheduling is working, they should start and complete at\n");
	printf("         about the same time\n");

	pthread_join(get_primes2_thread, &result);
	pthread_join(get_primes1_thread, &result);
	printf("rr_test: Done\n");
}

#endif /* CONFIG_RR_INTERVAL */
